Biomedical subjects
F A Burgener
Publications and source records attributed to F A Burgener.
1977 Memorial Award Paper. Renal renin and hemodynamic responses to selective renal artery catheterization and angiography.
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Mesenchymal hamartoma of the liver in an adult: radiologic diagnosis.
A case of mesenchymal hamartoma of the liver in a 30-year-old female is reported. Ultrasonography, computed tomography, and hepatic angiography demonstrated the presence of a large, mixed cystic and solid mass within the liver, suggesting the diagnosis of a mesenchymal hamartoma. At surgery, the tumor proved to be unresectable.
Experimental intrahepatic portocaval shunts created in portal hypertension by balloon angioplasty catheters.
Nonsurgical intrahepatic shunts between the left portal vein and left hepatic vein were created in seven dogs with portal hypertension by means of a Grüntzig angioplasty catheter with a balloon diameter of 12 mm. This catheter was introduced coaxially through a stiff 18-French Teflon catheter (diameter, 6 mm) using transjugular approach. The procedure had to be repeated in weekly intervals up to five times (range, one to five times; average, 2.4 times) until an intrahepatic shunt remained permanently open. Animals with open intrahepatic shunts were followed for one month to one year. Immediately after production of an intrahepatic shunt, the portal pressure fell from 23.7 +/- 3.5 cm of water to 10.6 +/- 1.4 cm of water, and remained in that range during the follow-up period. Portal blood flow increased at the same time from 9.1 +/- 2.9 mL/min/kg to 15.1 +/- 3.5 mL/min/kg. One week after successful shunt production, a second, more gentle rise of portal flow began. It lasted several weeks and was accompanied angiographically by a corresponding increase in shunt diameter. At necropsy, a smooth transition between the intima of the portal and hepatic vein and the shunt was found. Histologically, the endothelialized shunt consisted of granulation tissue with collagen deposition at one month and of fibrous connective tissue three months and later.
Treatment of experimental adenocarcinomas by percutaneous intratumoral injection of absolute ethanol.
Percutaneous injection of absolute ethanol into adenocarcinomas implanted in the hind leg of rats was evaluated as a potential cancer treatment. Intramuscular alcohol injections up to 10 mL/kg produced a local dose-dependent coagulation necrosis followed by granulation tissue formation and subsequent fibrosis but no apparent systemic side effects. Compared with controls, intratumoral alcohol injections induced partial to complete tumor necrosis, reduced the tumor growth rate, and caused complete tumor eradication in 25% of the cases. The therapeutic effects of the investigated dosages of 0.5 and 1.5 mL ethanol per tumor were similar, but the local side effects (fistulizations and/or neurologic damage) were increased with the larger dose. This preliminary investigation suggests that the percutaneous intratumoral injection of alcohol deserves further exploration for the treatment of cancers.
[Nuclear magnetic resonance tomography of the temporomandibular joint. Comparison with computerized tomography and arthrography].
79 patients aged 6 to 66 years (9 men and 70 women) with abnormalities of the TMJs were examined by magnetic resonance tomography (132 joints) and the results were compared with CT (16 joints) and arthrography (39 joints). Magnetic resonance tomography showed forward luxation of the meniscus in 82 joints (62%). In 34 joints (26%) the meniscus spontaneously resumed normal position when the mouth was open, but in 48 joints (36%) the displacement was permanent. The accuracy of resonance tomography was equal to that of arthrography and superior to CT. It was particularly suitable for follow-up examination after surgery (23 cases) when invasive arthrography would be contraindicated or difficult. Because of the high resolution of the soft tissue components in the TMJ, resonance tomography should be able to diagnose inflammatory and degenerative changes in the meniscus and ligaments.
Prostaglandins in diagnostic and therapeutic superior mesenteric artery pharmacoangiography.
The hemodynamic effects of prostaglandins PGA1, PGE1, PGE2, and PGF2 alpha on the splanchnic circulation were evaluated in five chronic dogs with portal hypertension, periportal fibrosis, and portosystemic venous shunting. The maximum effect was achieved with dosages of 2 micrograms/kg/min after bolus injection into the superior mesenteric artery. With this dosage a monophasic increase of portal blood flow and pressure was found with PGA1, PGE1, and PGE2, whereas PGF2 alpha caused a biphasic response: an initial decrease in portal blood flow and pressure was followed by an increase in these parameters. The average peak increase in portal blood flow and pressure was similar for PGE1 and PGF2 alpha, and significantly smaller for PGA1 and PGE2. Average peak iodine concentrations in the portal blood after superior mesenteric angiography were highest with PGF2 alpha, similar for PGE1 and tolazoline, and lowest in controls. The vasoconstrictor effect of PGF2 alpha is, overall, reduced and less reproducible when compared with vasopressin. This investigation suggests that both PGE1 and PGF2 alpha are effective for improved arterial portography, the latter agent appearing superior. On the other hand, PGF2 alpha cannot be recommended as a therapeutic agent for the treatment for gastrointestinal and particularly variceal bleeding.
Angiographic, hemodynamic, and histologic evaluation of portal hypertension and periportal fibrosis induced in the dog by retrograde biliary injections of sesame oil.
Periportal fibrosis and portal hypertension were induced by periodic retrograde biliary injections of sesame oil for two to three months in 12 cholecystectomized dogs equipped with Thomas cannulas. Stable portal hypertension between 18 and 24 cm of water occurred in four of 12 dogs (baseline: 10.4 +/- 0.5 cm of water); the remaining eight dogs required continuous biliary oil injections to maintain the portal pressure in that range. Portosystemic venous collaterals were first seen three weeks after the initial biliary oil injection and were extensively developed after two months. Hepatopetal portal blood flow decreased 61 +/- 5% during the first six months, with the greatest decrease of 32 +/- 4% occurring in the first month. Hepatic arterial flow did not change in the first month and then began to rise slowly to peak at nine months at 170 +/- 32% of its baseline value. The greatest increase in hepatic arterial flow was found between the sixth and ninth month when the portal flow no longer changed significantly. Hepatic fibrosis originating from the portal triads and around extravasated oil droplets appeared to progress slowly during the entire observation period. Animals with advanced hepatic fibrosis remained in satisfactory general health with liver enzymes usually remaining in the high normal to low pathologic range, allowing extensive follow-up examinations at regular intervals.
Comparison of diatrizoate, iopamidol, and ioxaglate for arterial portography. An experimental study in normal dogs and dogs with portal hypertension.
Diatrizoate, iopamidol and ioxaglate were compared in five normal dogs and in five dogs with presinusoidal cirrhosis and portal hypertension for arterial portography. After selective injection of 40 ml of each contrast agent in iodine concentrations of 320 mg per ml into the superior mesenteric artery, portal vein blood samples were collected in 2-second intervals and the iodine concentrations determined using x-ray energy spectrometry. The highest iodine concentrations in the portal blood were found in both normal portal pressure and portal hypertension with ioxaglate, followed by iopamidol and diatrizoate in this order. Compared with diatrizoate, ioxaglate and iopamidol increased the peak portal blood iodine concentrations 45% and 22%, respectively. The use of ioxaglate in arterial portography should show the portal system at least as well as when a conventional contrast agent is used together with a vasodilator such as tolazoline.
Correlation between portal blood iodine concentrations and radiographic visualization of the portal vein in arterial portography.
Portal blood iodine concentrations and the radiographic visualization of the portal vein were compared in five dogs (50 portograms). The portal blood iodine concentrations required for a certain degree of portal vein opacification varied considerably. However, an overall significant difference was found in the portal blood iodine concentrations of different degrees of portal vein visualization. An increase in the portal blood iodine concentrations from 0 to 30 mg per ml was associated with an overall improvement of the portal vein visualization. With a blood iodine concentration of 30 mg per ml, an excellent visualization of the portal system was always achieved that could no longer be improved by further increasing the portal blood iodine concentration up to 50 mg per ml. For a reliable diagnostic visualization of portal vein contributaries and branches, a blood iodine concentration of 30 mg per ml appears required; whereas for the visualization of the larger portal vein, 15 mg per ml appears sufficient.
Comparison of diatrizoate, iopamidol, and ioxaglate for the contrast enhancement of experimental hepatic tumors in CT.
The accumulation of diatrizoate and two new low osmolality contrast agents, iopamidol and ioxaglate, was investigated in three experimental tumors (a well differentiated mammary adenocarcinoma, a poorly differentiated colon carcinoma, and a hepatoma) in the rat. All three tumors were implanted into the liver 12 to 14 days prior to intravenous injection of the contrast agents in a dose of 300 mg iodine per kg. Iodine concentrations were determined in blood, liver, and tumors at 1, 5, 10, and 30 minutes using x-ray energy spectrometry. Ratios between tumor iodine and blood iodine concentrations increased more with time with diatrizoate than either iopamidol or ioxaglate and were at 30 minutes significantly greater for diatrizoate than the other two agents. This suggests that the contrast medium efflux from the vascular compartment into the extravascular compartment of all tumors is greater for diatrizoate than either iopamidol or ioxaglate. Although it is known from clinical experience that the differential enhancement between hypodense hepatic tumors and liver parenchyma decreases rapidly with time after contrast administration, this investigation suggests that the substitution of diatrizoate by either iopamidol or ioxaglate should not affect appreciably the contrast enhancement in this condition in dynamic CT completed within the first minutes after contrast administration. In a later phase, after contrast administration, however, both iopamidol and ioxaglate should conceal hypodense hepatic tumors less than diatrizoate.
[Production of nonsurgical intrahepatic portacaval shunt in portal hypertension using a Gruntzig balloon dilatation catheter].
Nonsurgical intrahepatic shunts between the left portal and left hepatic vein were successfully produced in 14 dogs with portal hypertension. Dilatation of the intrahepatic tract was achieved by means of a Grüntzig angioplasty catheter with an inflated balloon diameter of 12 mm. This catheter was coaxially introduced into the portal vein, through the 18 French catheter of a Dotter's coaxial catheter system placed initially into the portal system via transjugular approach. The intrahepatic portocaval shunts created in this fashion, proved to be effective in immediate reduction of increased portal pressure and no significant complications were encountered.
[Arthrotomography of the normal temporomandibular joint. Anatomy, technic and complications. I].
Most abnormalities in the T.M. joint are due to pathological processes in the meniscus or joint capsule. They usually manifest themselves as an anterior luxation of the meniscus, which cannot be demonstrated by conventional radiological examination, even including tomography. In order to evaluate the meniscus, it is necessary to perform a contrast examination of the inferior joint space. The technique has proved valuable in 280 patients (308 arthrograms). The method is described and radiological anatomy is discussed. There were no significant complications in our series.
[Arthrotomography of the pathological temporomandibular joint. II].
The findings in 308 TMJ arthrograms (280 patients) with selective contrast injection into the inferior compartment are described. An anteriorly luxated meniscus was diagnosed in 231 cases (75%). In 99 cases (32%) the meniscus returned to a normal position spontaneously during opening of the mouth, whereas in 132 cases (43%) the subluxation was permanent. In 108 patients (6%) with irreducible meniscus luxation, perforation of the meniscus or of the capsule was diagnosed, but in two cases this could not be confirmed at operation. The importance of early diagnosis for optimal treatment is discussed.
[Production of an intrahepatic portocaval fistula in the dog with liver cirrhosis and portal hypertension].
Non-Operative intrahepatic shunts between the left branch of the portal vein and hepatic vein were produced in 14 dogs with periportal cirrhosis and portal hypertension. Dilatation of the intrahepatic fistula was achieved with a Grüntzig catheter with a balloon diameter of 12 m. The catheter was introduced into the left branch of the portal vein passing through the right jugular vein, vena cava and hepatic vein by means of a co-axial system, using a stiff Teflon catheter with an external diameter of 6 mm. Repeated maximal inflation of the balloon, which was placed across the portal vein and inferior vena cava, produced an intra-hepatic portocaval shunt in all dogs. This resulted in immediate abolition of previously stable portal hypertension. The only significant complication was shunt occlusion within a week. In such cases the shunt was reopened by the same technique. The procedure had to be repeated at weekly intervals up to five times before a permanent intrahepatic shunt was established.
Contrast enhancement of hepatic tumors in CT: comparison between bolus and infusion techniques.
Pre- and postcontrast CT scans of 125 nonselected patients with histologically verified hepatic neoplasms were analyzed. Sixty patients received an intravenous bolus injection of 50-100 ml diatrizoate 60% in 10-20 sec, and 65 patients an intravenous infusion of 300 ml diatrizoate 30% in 5-10 min. Compared to the precontrast examination, a significant improvement in the visualization of hepatic tumors was obtained with both contrast administration methods when the patients were examined before the equilibrium phase (difference in blood iodine concentration between aorta and inferior vena cava of less than 10 H) is reached. The equilibrium phase is reached 2 min after a contrast material bolus and with termination of an infusion. Scanning in the equilibrium phase does not significantly improve visualization of hepatic tumors when compared to the precontrast examination and carries a considerable risk of partial to complete tumor concealment. For similar reasons, concealment of hepatic tumors might also result when intravenous contrast material is used for another radiographic study preceding the CT examination.
Contrast enhancement of focal hepatic lesions in CT: effect of size and histology.
The effect of size and histology on the contrast enhancement of hepatic lesions has been analyzed in this clinical and experimental investigation yielding the following results: (1) The attenuation values of hepatic cysts in patients increase significantly and inversely with their size after contrast enhancement when the cysts measure less than twice the CT-slice thickness. This seems to be caused by partial-volume effect. (2) Experimental tumors of identical sizes and originating from the same cell line can demonstrate different contrast-enhancement patterns. (3) Peak contrast uptake in both experimental and human tumors seems to be inversely related to their size. (4) Compared to liver, contrast washout from experimental and human tumors (presumably the extravascular space) is delayed. The delay in the contrast washout from a tumor seems to correlate with tumor size. These findings suggest that in general, it is not possible to differentiate reliably among various hepatic neoplasms on the basis of their contrast enhancement patterns for the following reasons: (1) Attenuation values of small hepatic neoplasms are distorted by partial volume effect. (2) Tumors of different histologies can demonstrate the same enhancement pattern. (3) Tumors of identical histology and size can demonstrate different enhancement patterns. (4) The enhancement pattern of a tumor changes with growth or size.
CT, including sagittal and coronal reconstruction, in the evaluation of pancoast tumors.
Seventeen patients with histologically proved bronchogenic carcinoma involving the superior pulmonary sulcus (Pancoast tumors) were evaluated by computed tomography (CT), including sagittal and coronal image reconstruction. Compared to conventional radiography, axial transverse CT images provided, in all cases, additional information regarding local tumor extension and metastatic spread. Mediastinal involvement either by lymphangitic spread or direct tumor extension was present in 11 cases. In 4 patients plain films clearly showed mediastinal disease; however, CT more clearly delineated overall tumor extent, thus facilitating improved therapy planning. In a further 4 cases CT showed mediastinal involvement after plain films had been read as normal, and in an additional 3 instances metastatic involvement was either greatly underestimated (2 patients) or overestimated (1 patient) on the plain films. Reconstructed images in sagittal and coronal planes lacked detail but facilitated a three-dimensional concept of tumor extent and relationship of tumor to adjacent structures, particularly major blood vessels.